• Title/Summary/Keyword: Autoclaving

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Effect of Addition of Ground Granulated Blast-furnace Slag on Strength Properties of Autoclaved Polymer-Modified Concrete (오토클레이브 양생 폴리머 시멘트 콘크리트의 강도성상에 미치는 고로슬래그 미분말 혼입의 영향)

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    • Journal of the Korea Concrete Institute
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    • v.14 no.4
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    • pp.608-614
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    • 2002
  • The effects of slag content and polymer-binder ratio on the strength properties of autoclaved SBR-modified concretes using ground granulated blast-furnace slag(slag) and a styrene-butadiene rubber (SBR) latex are examined. As a result, the compressive and tensile strengths of the autoclaved SBR-modified concretes using slag increase with increasing slag content, and reach a maximum at a slag content 40%, and increase with increasing polymer-binder ratio. In particular, the autoclaved SBR-modified concretes with a slag content of 40% provide about three times higher tensile strength than unmodified concretes. Such high strength development is attributed to the high tensile strength of SBR polymer and the improved bond between cement hydrates and aggregates because of the addition of SBR latex.

Bone Healing Properties of Autoclaved Autogenous Bone Grafts Incorporating Recombinant Human Bone Morphogenetic Protein-2 and Comparison of Two Delivery Systems in a Segmental Rabbit Radius Defect

  • Choi, Eun Joo;Kang, Sang-Hoon;Kwon, Hyun-Jin;Cho, Sung-Won;Kim, Hyung Jun
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.36 no.3
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    • pp.94-102
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    • 2014
  • Purpose: This study aims to validate the effect of autoclaved autogenous bone (AAB), incorporating Escherichia coli-derived recombinant human bone morphogenetic protein-2 (ErhBMP-2), on critical-sized, segmental radius defects in rabbits. Delivery systems using absorbable collagen sponge (ACS) and fibrin glue (FG) were also evaluated. Methods: Radius defects were made in 12 New Zealand white rabbits. After autoclaving, the resected bone was reinserted and fixed. The animals were classified into three groups: only AAB reinserted (group 1, control), and AAB and ErhBMP-2 inserted using an ACS (group 2) or FG (group 3) as a carrier. Animals were sacrificed six or 12 weeks after surgery. Specimens were evaluated using radiology and histology. Results: Micro-computed tomography images showed the best bony union in group 2 at six and 12 weeks after operation. Quantitative analysis showed all indices except trabecular thickness were the highest in group 2 and the lowest in group 1 at twelve weeks. Histologic results showed the greatest bony union between AAB and radial bone at twelve weeks, indicating the highest degree of engraftment. Conclusion: ErhBMP-2 increases bony healing when applied on AAB graft sites. In addition, the ACS was reconfirmed as a useful delivery system for ErhBMP-2.

Effect of ${Fe_2}{O_3}$ Addition on Mechanical and Optical Properties of t-$ZrO_2$/${Al_2}{O_3}$ Composites (${Fe_2}{O_3}$ 첨가에 따른 t-$ZrO_2$/${Al_2}{O_3}$ 복합체의 기계적 및 광학적 특성)

  • Lee, Deuk-Yong;Kim, Dae-Joon;Lee, Myung-Hyun;Park, Il-Seok;Choi, Hyun
    • Journal of the Korean Ceramic Society
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    • v.37 no.4
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    • pp.354-358
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    • 2000
  • Tetragonal (t)-ZrO2/Al2O3 composites doped with Y2O3, Nb2O5, and Fe2O3 ((Y, Nb, Fe)-TZP/Al2O3) were prepared over the range containing Fe2O3 from 0.1 to 0.5 mol% with 0.1 mol% intervals to evaluate the effect of Fe2O3 addition on chromaticity, hydrothermal stability, and mechanical property of the composites. After autoclaving for 20 h at 18$0^{\circ}C$ under 3.5 MPa water vapor pressure, no tlongrightarrowm phase transformation was observed probably due to the preferential solid solubility of Fe2O3 in Al2O3, the presence of the rigid Al2O3 particles, and the inherent phase stability of (Y, Nb)-TZP. The optimized strength and the fracture toughness of the composite were 700 MPa and 8.5 MPa.m1/2, respectively, when 0.1 mol% Fe2O3 was added. The composites have shown a gradual color change from a slightly white ivory to a pale yellowish brown with increasing the Fe2O3 concentration.

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Isolation and Characterization of Bacillus sp. Producing Broad-Spectrum Antibiotics Against Human and Plant Pathogenic Fungi

  • Chen, Na;Jin, Min;Qu, Hong-Mei;Chen, Zhi-Qiang;Chen, Zhao-Li;Qiu, Zhi-Gang;Wang, Xin-Wei;Li, Jun-Wen
    • Journal of Microbiology and Biotechnology
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    • v.22 no.2
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    • pp.256-263
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    • 2012
  • A strain of bacterium producing antifungal antibiotic was isolated and identification of the strain was attempted. We could identify the bacterium as being a Bacillus sp., based on morphological observation, physiological characteristics, and 16S rDNA sequence analysis, thus leading us to designate the strain as Bacillus sp. AH-E-1. The strain showed potent antibiotic activity against phytopathogenic and human pathogenic fungi by inducing mycelial distortion and swelling and inhibiting spore germination. The antibiotic metabolite produced by the strain demonstrated excellent thermal and pH (2-11) stability, but was labile to autoclaving. From these results, we could find a broader antifungal activity of Bacillus genus. Isolation and characterization of the active agent produced by the strain are under progress.

Effect of Heated Soybean on the Cholesterol Contents in Brain and Aorta of the Albino Rat (熱處理大豆가 흰쥐腦와 大動脈의 Cholesterol 含量에 미치는 영향)

  • Koh, Jin Bog;Lee, Kyung Ro
    • The Korean Journal of Zoology
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    • v.16 no.3
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    • pp.177-184
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    • 1973
  • The effect of heat treatment (autoclaving at $100^{\circ}C$ for 30 minutes) of soybean on the cholesterol contents in the brain and aorta of the albino rat was studied. The subjects were 72 young male rats and divided into 12 groups by diet and periods. Experimented periods were 5, 15 and 30 days, diet standard are raw soybean, soybean diets heated at $100^{\circ}C$ and $120^{\circ}C$ respectively, and each diet was prepared to contain 14g protein and 400 Kcal per diet 100g. After corresponding treatment, the cholesterols in the brain and aorta were determined. The results are summarized as follows: In the brain, total, free and ester cholesterol contents of each group are not remarkedly different from those of control group, in the experimental periods. In the aorta total and free cholesterol at $100^{\circ}C$ and $120^{\circ}C$ than those of control group, but there is no significant difference among groups fed for 15 or 30 days, and the ester cholesterol has no regular tendency. It seems that the heat treatment at $100^{\circ}C$ and $120^{\circ}C$ of solybean has no effect on the cholesterol contents of the brain and aorta.

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Characteristics Changes of Floury-type Rice depending on Water Immersion and Heat Treatment Time

  • Seon-Min Oh;Hyun-Jin Park;Yu-Chan Choi;You-Geun Oh;Jeong-Heui Lee;Jeom-Sig Lee;Hye Sun Choi;Jieun Kwak
    • Proceedings of the Korean Society of Crop Science Conference
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    • 2022.10a
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    • pp.314-314
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    • 2022
  • In the production of rice flour, wet milling is a method of milling rice after soaking it in water, and it takes a lot of time and cost from milling to drying. To overcome this problem, the floury type rice was developed for dry milling and it is known to have round starch granules, low content of damaged starch after milling, and a starch structure similar to wheat. Because of its unique properties different from normal rice, it is necessary to research on processing and characteristics of floury-type rice to expand its utility in the food industry. Therefore, this study aimed to prepare the pregelatinized floury type rice (Baromi2) by autoclave and investigate their physicochemical properties. As the heat treatment time increased, the brightness decreased from 83.8 to 76.8, however, both redness and yellowness increased from 0.57 to 4.5 and from 14.58 to 21.13, respectively. Despite of same treatment time, soaking in water (10 min) before autoclaving increased the solubility and swelling power of Baromi2 over 2 times. The peak viscosity of native Baromi2 was over 2000 RVU, on the other hand, there was a significantly decrease to less than 1000 RVU of pregelatinized Baromi2. Heat treatment without immersion caused partial gelatinization of starch, resulting that some starch granules maintaining their integrity. Whereas there were no starch granules in heat treatment with soaking in water due to complete gelatinization. This study would be helpful to the suggestion of using heat-treated floury-type rice as an intermediate material in the food industry in the future.

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Effects of Gamma Irradiation on the Shelf Stability of Whole Baked Egg (구운 계란의 감마선 조사에 따른 미생물학적 유통기한 설정)

  • Kim Dong-Ho;Song Hyun-Pa;Lee You-Seok;Cha Bo-Suk;Kim Byung-Keun;Byun Myung-Woo
    • Food Science and Preservation
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    • v.11 no.3
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    • pp.394-399
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    • 2004
  • The effects of gamma irradiation to improve the hygienic quality and microbiological shelf stability of whole baked egg were investigated by comparison with autoclaving process. The contamination levels of coliform, total aerobic bacteria and fungal group in a fresh egg were 10$^{5}$ CFU/g, 10$^{2}$ CFU/g and 10$^{1}$ CFU/g, respectively. After baking process, total aerobic bacteria and fungi were not exceeded to 10$^{1}$ CFU/g. Also, coliform was not detected under the aseptic process. However, cell counts of the baked egg after packaging reached to 10$^{4}$ CFU/g of total aerobic bacteria, 10$^{1}$ CFU/g of coliform, and 10$^{2}$ CFU/g of fungi. Therefore, it was assumed that microbial contamination of baked and packaged egg was mainly originated from an environmental uptake during packaging process. Microbiological shelf stability of the non sterilized control was about a week. Whereas, the baked eggs irradiated at more than 5 kGy were stable over 12 weeks at ambient condition as like those being autoclaved. Analytical texture profIle was stable within 10 kGy, but it became hardened in the sample treated with autoclaving. About 67$\%$ of panelists identified a sensory difference between non-irradiated and 10 kGy-irradiated sample. The baked egg irradiated at 10 kGy and autoclaved had lower acceptability than the control or samples irradiated lower than 5 kGy. Therefore, it was considered that optimal irradiation dose for radiation sterilization of baked and packaged egg was 5 kGy. At that point, it was recommended that appropriate microbiological shelf-life was 12 weeks at ambient condition.

Hydrothermal Synthesis of Kaolinite (캐올리나이트의 수열합성)

  • Jang, Young-Nam;Ryu, Gyoung-Won;Chae, Soo-Chun;Lee, Sung-Ki;Suh, Yong-Jae;Bae, In-Kook
    • Journal of the Mineralogical Society of Korea
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    • v.20 no.3
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    • pp.147-153
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    • 2007
  • Kaolinite [$Al_2Si_2O_5(OH)_4$] was successfully synthesized by a hydrothermal process from amorphous $Al(OH)_3$ and $SiO_2$ at $230^{\circ}C$ under the pressure of $30 kg/cm^2$. The experiments were performed varying temperatures ($180{\sim}280^{\circ}C$), pressure ($10{\sim}60kg/cm^2$), chemistry ($Al_2O_3/SiO_2 = 0.5{\sim}0.38$) and pH ($0.3{\sim}9.5$) of the solution. The autoclaving was carried out in a closed stainless steel vessel. Kaolinite appears from the starting composition of $Al_2O_3/SiO_2= 0.5$ with boehmite and was stable as a single phase with the composition of $Al_2O_3/SiO_2=0.45$. Boehmite was a stable phase below $200^{\circ}C$ for the 240 h period of autoclaving, but kaolinite appeared even in 20 h at $230^{\circ}C$. The single kaolinite phase of a good crystallinity was observed at pH ranging 2 to 6. That indicates that pH is one of the most critical parameters for the successful formation of kaolinite. The optimal molar ratio of $Al_2O_3$ to $SiO_2$ was determined to be 0.45. The XRD pattern of the synthesized kaolinite coincided with that of natural one and its morphology was the cluster type of the kaolinite crystals (diameter = ${\sim}3{\mu}m$), irrespective of starting material, composition and temperature.

Formation of Enzyme Resistant Starch by Extrusion Cooking of High Amylose Corn Starch (고아밀로즈 옥수수전분의 압출성형에 의한 난소화성화)

  • Kim, Ji-Yong;Lee, Cherl-Ho
    • Korean Journal of Food Science and Technology
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    • v.30 no.5
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    • pp.1128-1133
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    • 1998
  • Extrusion cooking treatment was compared with autoclaving/cooling treatment for formation of enzyme resistant starch of high amylose corn starch (HACS). Effects of barrel temperature $(100^{\circ}C,\;120^{\circ}C,\;140^{\circ}C)$ and feed moisture content (25%, 35%, 45%) on extrusion processing in a co-rotating twin-screw extruder under fixed screw speed (100 rpm) were investigated by measuring enzyme resistant starch (RS) yield. RS yield were estimated by in-vitro pancreatin digestion method and enzymatic-gravimetric method using termamyl. Barrel temperature and yield of RS were negatively correlated and feed moisture content and yield of RS was positively correlated as determined by in-vitro pancreatin method. The highest yield (38.4%) of RS was obtained from HACS extrudate processed at the barrel temperature of $100^{\circ}C$ and the feed moisture content of 45%, while the yield of RS by 5 times of autoclaving/cooling was 25%. The yield of RS by in vitro pancreatin digestion method was 20.7% with high amylose corn starch and 8.2% with ordinary corn starch (CS), respectively, under the same extrusion condition (barrel temperature $120^{\circ}C$, feed moisture content 35%). At the same condition, the yields of RS by enzyme-gravimetric method were 14.6% with HACS and 6.8% with CS, respectively. The yield of RS increased during the storage at $4^{\circ}C$ for 4 weeks and the highest yield (60%) was obtained by the storage of HACS extrudates extruded at $100^{\circ}C$ and 45% feed moisture content.

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Anti-Allergic Inflammatory Effect of Bacteria Isolated from Fermented Soybean and Jeotgal on Human Mast Cell Line (HMC-1) (장류 및 젓갈 분리 균주 추출물의 비만세포 매개 항염증효과)

  • Ko, Yu-Jin;Kim, Hui-Hun;Kim, Eun-Jung;Kim, Jin-Yong;Kang, Sang-Dong;Son, Yong-Hwi;Choi, Sin-Yang;Cha, Seong-Kwan;Kim, Jong-Won;Lee, Jeong-Ok;Ryu, Chung-Ho
    • Journal of Life Science
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    • v.21 no.3
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    • pp.393-399
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    • 2011
  • The mast cell is one of the major effector cells in inflammatory reactions and can be found in most tissues throughout the body. Activated mast cells can produce histamine, as well as a wide variety of other inflammatory mediators such as eicosanoids, proteoglycans, proteases, and several pro-inflammatory cytokines, such as tumor necrosis factor (TNF)-${\alpha}$, and interleukins (IL-6), IL-8, IL-4, IL-13. In the present study, we isolated two bacterial strains (J80 and G147) from fermented soybean and Jeotgal, and investigated the inhibitory effects of their extracts which were prepared by several pretreatment methods (sonication for 20 min, heating at $100^{\circ}C$ for 30 min, autoclaving at $121^{\circ}C$ for 15 min) on the mast cell-mediated inflammatory response. The pretreated bacterial extracts had no cytotoxicity against Human Mast Cell (HMC-1). Among various pretreatments, the extracts treated at $100^{\circ}C$ showed highest inhibition of histamine release (J80, 28.46%; G147, 41.14%). The J80 and G147 extracts treated at $100^{\circ}C$ resulted in the inhibition of IL-6 secretion by 38.46% and 56.45%, respectively. The J80 extract treated at $100^{\circ}C$ resulted in the inhibition of TNF-${\alpha}$ secretion by 66.67%, but G147 extract showed the highest inhibition effect by 41.1% when treated with sonication. These results suggest that bacterial extracts treated at $100^{\circ}C$ have a higher level of anti-inflammatory effects than other treatments such as sonication or autoclaving.